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Jens Axboe On Kernel Development

Posted by ScuttleMonkey on from the nuts-and-bolts dept.

BlockHead writes "Kerneltrap.org is running an interview with Jens Axboe, 15 year Linux veteran and the maintainer of the linux kernel block layer, 'the piece of software that sits between the block device drivers (managing your hard drives, cdroms, etc) and the file systems.' The interview examines what's involved in maintaining this complex portion of the Linux kernel, and offers an accessible explanation of how IO schedulers work. Jens details his own CFQ, or Complete Fair Queue scheduler which is the default Linux IO scheduler. Finally, the article examines the current state of Linux kernel development, how it's changed over the years, and what's in store for the future."

5 of 68 comments (clear)

  1. CFQ not the default scheduler? by rehabdoll · · Score: 4, Informative

    Anticipatory is, according to my menuconfig:

    The anticipatory I/O scheduler is the default disk scheduler. It is
    generally a good choice for most environments, but is quite large and
    complex when compared to the deadline I/O scheduler, it can also be
    slower in some cases especially some database loads.    *

    Anticipatory is also preselected with a fresh .config

    1. Re:CFQ not the default scheduler? by zdzichu · · Score: 4, Informative

      CFQ is default since 2.6.18, released back in September 2006.

      --
      :wq
  2. Re:Wow ... by Error27 · · Score: 3, Informative

    Marcello was only 18 when he took over the 2.4 branch. He was working for Conectiva at age 13 or 14... Debian has had a bunch of really young package maintainers for critical packages.

  3. Re:Missing Question: How do you pronounce your nam by axboe · · Score: 3, Informative

    Hi John!

    That is correct, like a "y", rhymes with "mens". I saw another question on the lastname, I typically tell foreigners that it is pronounced ax-bow. Europeans often think the 'oe' is like the Danish "ø", however that is not the case.

  4. Re:Scheduling better than no scheduling? by axboe · · Score: 3, Informative

    It depends on what you need to schedule. If your drive does queuing and only one process IO is active, then the OS can do very little to help. The OS usually has a larger depth of ios to work with, so it's still often beneficial to do some sorting at that level as well.

    IO scheduling is a lot more than that, however. If you have several active processes issuing IO, the IO scheduler can make a large difference to throughput. I actually just did a talk at LCA 2007 with some results on this, you can download the slides here:

    LCA2007 CFQ talk